Process of distilling oil



uy E, 1924i.

J. J. ALLINSON PROCESS 0F DISTILLING OIL Filed July 17. 1919 2Sheets-Shee?. l

July l 1924.

J. J. ALLINSON PROCESS OF DISTILLING OIL 'JOHN JOSEPH ALLINsoN, orBAarLEsvILLE, ox' I:

l 1,500,040 NT oFFlcr.o

OMA, ASSIGNOR, BY MESNE AS- i SIGF'MENTS, T0 DOHERTY RESEARCH COMPANY,0F NEW YORK, N. Y., A CORPORA- .rxon or DELAWARE raoosss .or Dis'rrLmNe'om Applieauon mea my' 17, 1919. serial so. 311,558.

To'all whomtmay concern: Be it known that I, JOHN JOSEPH ALUN- soN, acitizen of the United States, residing at Bartlesville in the county ofWashington, State of lklahoma, have invented certain new and usefulImprovements in Proc'- esses of Distilling Oil; and I do hereby de- 1clare the following to be a full, clear, and

exact description -of, the invention,y such as l0 will enable othersskilled in they art to which it a pertains to make and use the same.

T is invention relates to oil distillation and more particularly to aprocess of distilling oil by which the lighter constituentsA lyexpedited and the capacity of the stillsy is increased. In the usualtopping plant, the fresh crude oil is ordinarily heated under ressure ina still or retort andthe heated 011 islthen passed into a largerchamber.

to allow the lighter constituents to vaporize. The vapors formed inthechamber are then conducted to a condenser and the oil remaining in thecondenser is conducted to the stills for complete distillation.- Thequantity and character of vapors obtained by such topping processesdepend upon the kind of oil being treated and the temperature andpressure of .the oil entering the vaporization chamber. Therefore, suchprocesses do not provide an accurate and com lete removal of the lightconstituents of t e oil so *hat -a further removal of the lighterconstit" 1`1....ts4

v 36 which acts through a plpe 38, vacuum must also be made in thestills. A The primary object of the present invention is to provide aprocess of distilling crude etroleum oil in which the removal of thelighter constituents of the oil ma be efciently carried out and accuratey controlled.v

Another object of the invention is to provide a process of distillingoil under 'a vacuum pressure which may be effectively used in acontinuous oil distillation treatment.

With these and other objects in view, the

invention consistsl in the improved process of distilling oilhereinafter described and Aparticularly ,defined in the claims.

rlhe various features of the invention are illustrated in theaccompanying drawings,A

in which, l

' Figure 1 is a diagrammatic View in front elevation illustrating anapparatus in which a process of distilling oil embodying the preferredform of the inventionmay be carried out;

Fig. 2 is a view -in vertical section of the improved vacuum still; and

A F-ig. 3 isa lview in side elevation of the vacuum still. l

` The improved process of distilling oil embodying the preferred form ofthe in-` -Ventzio'n my be carried out in the apparatus shown in ig. 1as-follows: Crude oil from storage is conducted through a pipe 10 to apump 12 and forced through a heat inter-- changer14. The `oil is heatedin the interchan er to a temperature of from 200 to 300o depending uponthe temperature of the residuum oil iiowing through the interchanger,and is then conducted through a pipe 16 'to fthe upper portion of avacuum still18. The oil underA a sli ht pressure from the pump l2 entersthesti 18 through -a distributor 2O :and is broken -up into aiine sprayby the d-istri-butor.- When the oil is released in the still 18 intheform of fine s ray, it starts'to vaporize and the vaporizat1on of theoil is carried out in a series of stages, there being one stage for eachof the com artments 22z 24, 26, 28,- 30, 32 and 34.

of t e vacuum Stull. The vapors formed'in the various com' ar-tments ofthe y uum still are positive y drawn out of the compartments under avacuum suction. vacuum suction is created by a vacuum pump trap 40, pipe42 and conduit v,44 to draw the vapors out of the compartments intovapor- The in the box 64 are removed through a pipe 68 and pass tostorage. The vapors condensed in the trap 40 and dephlegmator 56 and 58are removedthrough a pipe 70 and pass to storage.

Y out through a pipe 7 2by means of a pump 74 and forced through apipe'7 6 into a fire. still 78 which forms the first of a series of firestills 78, 80 and 82. The lire stills 78, 80 and 82 may be operated inthe usual manner to remove. the various fractional condensates from thepetroleum oil. In the operation of the fire stills, it may beadvantageous to admit steam with the oil passing through the stills inorder to assist in carrying on the fractional distillation. Although thestills 78, 80 and 82 have been described as lire stills, these may beany of the approved forms of stills for carrying on d1stillation by theapplication/,of heat.- The residuum oil left in the s ll 82, whlch 1susually called fuel oil, is emoved through a pipe 84 and passes throughthe heat interchanger 14 to the act as l'a heating medium for preheatingthe fresh crude oil enterin through the pump 12. -The volume antemperature of the residuum entering the heat interchanger through thepipe 84,1s carefully regulated so that the oil passing through theinterchanger will havepa sufliciently high temperature to permit the/lighter constituents of fresh crude bil to be removed in the vacuum4still 18. The fuel oil which is cooled in the heat interchanger 14passes out through a pipe 86 through a pump 88 and may be conducted tostorage through a pipe 90.

The construction of the vacuum still 18 is shown more particularly inFigs. 2 and 3. The still 18 consists of an elongated cylindrical tankwhich is builtnp in sections connected by gas and vaporr tight joints.The compartments 22, 24, '26, 28, 30, 32 and 34 of the vacuum still areseparated by means of fine mesh screens 92 which are supported uponangle iron frames 94 mounted within the still. With this construction,the oil is broken into a fine spray as it enters the top of the vacuumstill through the distributor 20, and the non-vaporized oil is collectedon thescreen 92 below the distributor. While the oil passes through thescreen 92 to enter the compartment 24 from the compartment 22, it isbroken up into fine drops and is thus in a fine drop or spray in passingthrough -the compartment 24. In this way, the oil is broken up into nedrops 'by the screens 92 in passing from one compartment 't0 the nextlower succeeding compartment. The

screens 92 divide the oil into a 'very large number of ne'particleswhich expose a very large surface of the oil and thus expedite thevaporization. To further assist in the vaporization, the oil vapors arewithdrawn under vacuumfrom each compartment of the still and any of thelighter constituents in the oil which are not removed in the uppercompartments may be removed into the lower compartments and drawn intothe vapor-collecting pipes 46 and A48. The vapor is collected from thecompartment 22 through pipes 94 which are connected with the collectingpipe 50. The inner ends of the pipes 94 are provided with perforatedspherical members 96 which act to screen the vapors passing into thepipes 94 and preventliquor from being drawn into the collecting pipe 50.The vapors are withdrawn fromthe compartments 24, 26, 28, 30, 32 and 84through tubes 98 which are mounted at opposite sides of each of thecompartments and connected with Ts 100` mounted in the vapor-collectingpipes 46 and 48. Over the end of each of the outlet pipes 98 are mountedbaies 102 which prevent the liquor passing through the compartments frombeing drawn directly into the pipes 98. Below each of the bales 102 andacross the inlet ends of the pipes 98 are 00 are connected respectivelywith the tubes 98 and the vapor-collecting pipes 46and 48. Any liquidoil which reaches the vapor-collecting pipes 46 and 48 will be held backby the screens 106 and will flow downwardly y gravity through thevapor-collecting pipes and be discharged into the vaporizing compartment34.

As shown in Fig. 3, man-holes 108 are mounted at the upper and lowerends of the vacuum stlll 18 to permit access to the interior of thestill.

With. the .process and apparatus described above, 1t will be seen thatthe lighter constituents of petroleum oil may be effectively removedfrom the oil without the use of heat other than the heat 'in theresiduum leaving a series of heating stills. Although 1t is best tomaintain a sucient volume and quantity of residuum to raise the tem#perature of the oil owing to the vacuum Still above 200, it is notessential that the oil entering the vacuum still shall be at such aihigh temperature because if the temperature of the oil entering thevacuum still is low, the vacuum pressure within the still may bematerially reduced to insure that an 0i the. nghter constituents win beremoved from the oil. With this arrangement, further, it is notnecessary that the i' temperature of the oil entering the vacuum stillshall be uniform in order to efficiently removev the lighterconstituents, but any combination of temperature and vacuum/constituents, the oil passing through each of the zones being in theform of a ne spray or dropse 4 Heretofora many attempts -have been madeto provide a' continuous distillation of petroleum under a vacuum.However, a continuous process of distillation under a vacuum has notbeen carried out on account of difficulties and limitations ofmechanical construction involved in the operation of a vacuum still.With the improved process described above, however, a vacuum separationof the lighter constituentsmay be effectively carried out in acontinuous distilling operation.

Although the residuum Withdrawn from the still 82 is used for preheatingthe fresh crude oil passing through the vacuum still, the fractionaldistillates coming from the stills 78, 80 or 82 may be used in the heatinterchanger 14 for preheating the crude oil.-

The preferred form 'of the invention having been thus described, What'isclaimed as new is:

1. In the distillation of crude petroleum the steps comprising heatingpetroleum oil,

passing the heated oil through ya series of compartments maintainedunder a partial vacuum, finely dividing said oil at the points of itsadmission to sa1d compartments, vaporizing the lighterportions of theoil enclosed in said compartments by the vacuum in said compartments,separately Withdrawing vapors directly from each of said compartmentsout of contact with the oil in the said chamber and condensing the saidvapors.

2. In` the distillation of crude petroleum the steps comprisingimparting a preliminary heat to crude oil of a temperature be- .low 300F.,lpassi'ng the heated oil into a chamber and finely dividing said oila pluralityl ofI times Within said chamber, vaporizing the lighterportions of the oil enclosed in the'chamber solely by the sensible .heatkof the oil and the maintenance of a partial vacuum in the chamber,removing the 'vapors by suction as they are formed in the chamber,removing residual oil from the chamber and subjecting it to fractionaldistillation and imparting preliminary heat to the incoming-crude oil bya heat interchange with hot residual oil from the fractionaldistillation. Y

3. In the distillation of crude petroleum the steps comprising heatingpetroleum oil to a temperature between 200o and 300 F., spraying the oilprogressively into a series of compartments maintained atsub-atmospheric pressure, vaporizing a portion of the said oil in thesaid compartments by means of the sensible heat of the oil, Withdrawingthe vaporized oil as soon as it is formed,

'and condensing the said vapors.

In testimony whereof I aiiix my. signature.

JoHN JosEPH'ALLiNsoN.

